AN INVESTIGATION is underway into the US tax activities of several of the world’s largest private equity groups.

The firms include Republican presidential candidate Mitt Romney’s (pictured) former company Bain Capital, KKR and Apollo Group, and will be investigated over strategies which could have allowed them to avoid millions of dollars in US taxes, a person familiar with the case told the Financial Times.

The probe will be led by New York’s attorney-general, Eric Schneiderman, who is a Democrat.

One private equity executive, cited by the Financial Times, said: “This is shamelessly political, but it’s to be expected and I’m surprised it hasn’t happened sooner.

“You have a right to privacy, but you don’t have a right to be president. If Bain and Mr Romney saved themselves tens of millions of dollars in taxes, you would expect them to be examined.”